This is a link to Judith Lean's recent paper on multiple regression analyisis of major modes of climate variability. She uses ENSO, anthropogenic influences, solar variability and volcanic aerosols. Judith Lean's methodology is given in a 2007 paper (reference 22) also freely available.
http://www3.interscience.wiley.com/cgi-bin/fulltext/123222295/PDFSTART I quite like Judith Lean's paper - I think it is a model of clarity. I think the methodology is hugely promising. Simple, robust, refreshingly empirical and captures a major aspect of nonlinear climate variability through ENSO. And yes I do note that she concludes that anthropogenic influences are predominant. I don't think she is wrong as such - although the forward projection is dodgy enough to be amusing. It does show convincingly the problematic nature of climate projections. We should anticipate the cooling influence of ENSO on this decade's temperatures to continue for a while yet. Our abilities to predict volcanos decades in advace is obviously not huge at this stage. Solar variability should be projected as probabilities of change rather than as a copy of cycle 23. I do think there is another obvious influence on climate that should be included in the multiple regression analysis. See the discussion on clouds at Professor Ole Humlum's site - http://www.climate4you.com/ClimateAndClouds.htm Cloud cover decreased by about 5% from the mid 1980's to 2000 and has increased about 3% since on ISCCP-FD data. That is about 0.3 degrees net warming to 2000 and 0.18 degrees net cooling since. A major influence by any estimation. This is more likely to be largely an ENSO feedback rather than a 'global warming feedback' - but nonetheless should be included as a factor in the regression analysis. Cheers Robert -- You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/globalchange
